Pump, compressor, or blower



Sept; 2 1924. 1,506,893

F. EGERSDORFER PUMP, coMPnEssoR, on BLowzn Sept. 2. 1924. -Lsos F.EGERSDORFER PUMP, COMPRESSOR, OR BLOWER Filed Dec. 13, 1922 Zhnen-Shoot2 Patented Sept.j2, 1924.

UNITED STATES.' PATENT orales.

rm'rz nennsnnrnn, or cHAaLofr'rENBURG, GERMANY.

ruin, oomraasson, or. BLOWER.

Application le'd December 1.3, .1922. Serial No. 606,704.

To all whom z't may comer/n.'

Be it lmown that I, Fnrrz Eennsnnrnn, a citizen of Germany, residing atCharlottenburg, in the State of Prussia, Germany, have invented certainnew and useful Improvements in Pumps, Compressors, or Blowers (for whichI have filed an application in Germany); and I dohereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

My invention relates to improvements in pumps, compressors, or blowershaving revolving plungers or pistons, and consists more particularly inmeans for tightening the members containing the ports which in operationcome intermittently 'into registry and in so doing control the supplyand discharge of the fluid. As is known in the art it is diicult toprovide a tight fitting between the surfaces of these members, which,subiect to wear, are forced apart by pressure of iiuid getting betweenthe same. Practically it is impossible in most cases by the provision ofextraneous means to hold the said members in tightening engagement witheach other. for the .reason that the Apower required for forcing theparts together cannot be rendered variable to accord with the varyingseparating tendency, The invention consists in holding the said -membersAtogether by thepressure of the @uid compressed bythe pump acting on oneofthe said members which for this purpose is yieldingly mountedrelatively to the othermember. In case the pistons or plungers aremounted in pockets or cylindrical bores formed in a drum rotaryv withina casing (one of the members containing Athe controlling ports), thepressure fluid is made to act on the remote face of the drum. In anycase the same Huid pressure which, effective between the parta-tends toseparateV them, is made effective upon them in such manner also that,tending oppositely, it cancels the tendency first mentioned. Thecompensating tendency therefore is automatically adapted lto varying..condif bers even at this time exceeds the uid pressure tending toseparate the controlling sur faces. For the purpose, of explaining theinvention two examples embodying the same have been shown inthe"accompanyingdrawings. in which- Fig. 1, is a cross-section of an aircompressor having a rotary drum provided with radially reciprocatingplungers, the section being taken on the line 1-1 of Fig. 2,

Fig 2, is a longitudinal section taken on the line 2--2 of Fig. 1,

Fig. 3, is a detail view showing one of the controlling members and theports thereof,

Fig. 4, is a longitudinal section of a liquid pump taken on the line 4-4of Fig. 5,

Fig. 5, is a cross-section taken on the line 5 5 of Fig. 4,

Fig. 6, is a detail sectional -view taken on the line 6-6 of Fig. 4, and

Fig. 7, is a detail view showing one of.

the controlling members and its ports.

In the example shown in Figs. 1 to 3, within a casing 1, a drum 2 islocated. which is keyed or otherwise secured to a shaft 7 rotatablymounted in a bearing 8 provided inone of the end walls of the casing 1.The drum 2 is formed with three radial cylinders 3 having pistons orplungers 4 reciprocating therein'. and the cylinders are connected byouter flanges 5 and an inner ange 6. One of the end walls of the drum isconstructed for providing one of the controlling surfaces, and it is.traversed by the cylinder ports 9. The said controlling surface isengaged by a block 12. In block 12 A ports 10 and 11 are'formed. Block12 is mounted in casing 1, it is secure against rotation, but it iscapable of sliding in the direction of the axis of drum rotation. Theblock is at all times subiect to the tension of a spring 14 which,supported from behind by a plate 13, tends always to hold the block inclose engagement, surface to surface, with drum 2. The plate 13iscarried by casing 1, ,and is perforate, as at 16. Rearwardly of plate13 the casing contains a chamber 17 which` faced with a sieve 15, may befilled with a loose filtering medium, such as cotton or the like. 17opens to the pressure passage 18 for Huid from the pum l Y The shaft 71s eccentrically mounted witlv This chamber in the casing 1, and whenthe same is in rotation the reciprocating plungers 4 are thrown bycentrifugal force against the inner face of the cylindrical part of thecasing, which casing is disposed 'eccentrically of the axis of the drum2. This eo'centrically disposed inner Wall of casing 1 therefore permitsoutward centrifugal movement of the plungers during one half of therotation of the drum for performing the suction stroke, and during theother half of the rotation forces the plungers inwards for performingthe pressure stroke. such rotation the surface of drum 2 upon whichblock 12 bears, slides upon the face of block 12, and the cylinderports`9 comeinto alternate and 'successive registrv with the suction andpressure ports 10and 11 of the controlling slide 12. The segmentalsuction port 10 in block 12 extends through a large part of a circle,While the pressure port 11 through which the air compressed Within thecylinder is delivered, is in the form of a small circular bore.Consequently the plungers lare not during the larger part of thepressure stroke subject to the v pressure of the air which has beforebeen compressed.

The spaces beyond port 11 and between port 11 and the pressure passage18 constitute a chamber formed Within the frame and closed by the slide12, and this chamber is constantly under the pressure of the compressedair. The block 12 consequently is constantly subject to that pressureand impelled by the said pressure from its rear face to its engagementupon the corresponding surface ofthe drum, so that a tight joint isproduced between the contacting surfacesby the pressure of thecompressed air. To this pressure the tension of the spring 14 is added,so that any air which might get from the ports 9 between the contactingsurfaces can in no case unseat the block 12.

The suction port 10 is in vcommunication with the inner parts of thecasing 1, so that the plungers take the-air from the said casing. -Theair is admitted through apertures 19 and 2O made in the end Walls of thecasing and covered by sieves. Therefore the inner parts of the pump arecooled by the fresh air supply. By the sieve 15 and the filtering mediumconfined Within the chamber17 the compressed air is cleaned from oil andother impurities. The block 12 is tightened in its sliding engagementwith the Walls of the pump casing by packing 21.

1n the modilication shown in Figs. 4 to 7 the plungers -34 reciprocatein axial direction Within bores or pockets made in a drum 32 `rotatablymounted Within a cylindrical casing 31. As shown three plungers 34 areprovided which are connected to cylindrical During Lacasse slide blocks42, as is best shown in Fig. 4, which slide blocks are engaged by arms43 of a vstar shaped rocker having universal connection With the drum 32by means of a spherical journal 44. The blocks 42 are formed at theirends with spherical cavities engaged by semi-spherical slide shoes 45engaging an inclined disk 46 adapted to be set yin dijd'erent angularpositions relatively to the axes of the plungers 34 for varying thestroke of the plungers, as is known in the art.

The driving shaft v37 carries a coupling member 47 formed with threearms each engaging a leaf spring 48 secured to cylindrical rockers 50mounted in longitudinal bores 49 of the drum 32. Within the said borescoiled springs 51 are located which tend to force the rockers 50outwards and into Contact With the coupling member 47. By reason of thisclutch mechanism the drum 32 which is rotatably mounted on a shaft 52ils slightly yielding in circumferentialand. longitudinal direction rclatively to the driving shaft 37.

The chamber 53 enclosing the driving mechanism is made air tight by the,pump casing 31 and the drum 32, and it is in communication through aduct 54 with a cylindrical chamber 55. The -side of the casing which isopposite to the chamber 53 is closed by a controlling disk or head 30secured to the casing 31 and formed with segmental -suction and pressureports 59 and 58 and suction and pressure passages 56 and 57. In case thepumpis designed for supplying liquid, the said ports extend through acomparatively large part of the circle, as is shown in FigQ7. .A duct36l connects the passage 57 .with the chamber 55. If the said chambersand passages are iilled with the compressed liquid pressure of theliquid Ais transmitted to the rear face of vthe drum v32, the pressureon the rear face of the drum corresponding to the pressure of the liquidacting on the front tace. formed with the controlling ports and holdingthe drum in conta-ct with the controlling disk or head 30.

As shown in Fig. 4. Within the. chamber 55 a plunger is mounted. whichhas the function to take up the pulsations imparted. as the pumpoperates, to the liquid Within the column of passage 57, so that suchpulsations are not transmitted to the chamber 53. This is effectedeither by the inertia of the plunger or by providing a plunger yieldingby elasticity Without transmitting the shocks from the pressure side tothe chamber 53. example shown in Fig. 4 the plunger is made in twosections 60 and 61 having a spring 62 disposedbetween the same. lf apulsation is imparted to the liquid Within the passage 57, suchpulsation is transmitted' the In the Lacasse through the duct 36 to theliquid confined within the left hand part of the chamber 55 and to thesection r60 of the plunger bounding the same. This section 6() isthereby shiftedl` compressing the'spring 62. Upon the passing of thepulsation the spring 62 returns the section 60 vinto initial position.If however the increased pressure endures the spring 62 advances' the.section 61 so as to transmit the increased pressure to the chamber 53.Vhile the'apparatus is under pressure the spring 62 is always undertension. Therefore the plunger 60, 61 has the function of apower-storing member adapted to absorb pressure when the pump isdelivering liquid through the passage 57.

vThis function is important for example in case the pump is in use as afuel feed'pump for an internal combustion engine, for throwing measuredamounts of fuel intothe cylinders of the engine. ln such case shortrepeated pulsations of pressure are imposed on the liquid, which blowsare taken up by the plunger 60, 61. Furthermore by reason of the powerstoring capacity the plungers assist the discharge `of the individualfuel charges.

Tn the example shown in Figs. 4 to 7, in addition to the pressureproducing plungers 34. plungers 40 are provided. These also areconnected with theJ blocks 42. These plungers 40 are smaller in diameterthan the plungers 34. They cooperate with controlling ports 41 and 41'.The object of these subsidiary plungers is to supply a second liquidunder pressure,

which is discharged independently of the main liquid cischarge oradmixed thereto, in which case the pressure port 41 is in communicationwith the pressure passage 57, as is shown in Fig. 4.'. Therefore theplungers 34 can be used for supplying fuel to an internal combustionengine, while the plungers 40 are used for supplying a certain amount ofwater to the said fuel.

1n both examples the segmental controlling ports of the stationary disk30 (12) may be arranged with slight eccentricity of the axis withrespect to the rotary drum, so that the cooperating ports of thecontrolling members 32 and 3() (2 and 12) may come gradually to positionfor full cooperation.

While in describing the invention reference has been made to particularexamples embodying the same 1 wish it to be understood that my inventionis not limited to the constructions shown in. the drawings, and thatvarious changes may be made in the general arrangement of the apparatusand the construction of its parts without departing from the invention.

I claim:

1. In a pump, compressor, or blower, the 'combinationl with a frame, amember formed with a cylindrical pocket, a piston within said pocket,means to control the reciprocating movement of the piston wit in saidpocket, `a member formed with suction and pressure ducts adapted to bealternately thrown'into and out of communication with said pocket, meansto impart relative rotary movement to said member and frame, said frameforming with said meinber a chamber communicating with said pressureduct andin position to enable the fluid pressure admitted from thepressure duct to said chamber to force said member and frame intoengagement for tightening said ducts, and pressure-balancing meansintermediate said pressure duct and cham- 2. In a pump, compressor, orblower, the combination, with a frame, a member formed with acylindrical pocket, a pistou within said pocket, means to control thereciprocating movement of the. piston with- .in said pocket, a memberformed -with suction and pressure ducts adapted to be alternately throwninto communication with said pocket, and means` to impart relativerotary movement to said member andV frame, said frame forming with saidmem- `ber a chamber communicating with said pressure duct and inposition to enable the Huid pressure admitted from the pressure duct tosaid chamber to force said member and frame into engagement fortightening said ducts, of elastic means acting in the direction of theluid pressure within said chamber and forcing said member and frame intotightening engagement, and pressure balancing means intermediatepressure duct and chamber.

3. In a pump, compressor, or blower, the combination, with a frame, amember within said pocket, means to control the reciprocating movementof the piston within said pocket, a member formed with suction andpressure ducts adapted to be alternately thrown into communication withsaid pocket, and means to impart relative rotary 'movement to saidmember and frame, said frame forming with said member a chambercommunicating with said pressure duct and in position to enable thefluid pressure admitted from the pressure duct to said chamber to forcesaid member and frame into engagement for tightening said ducts, andpressure-absorbing means arranged in the line of communication betweensaid pressure duct and chamber.

4. 1n a pump, compressor, or blower, the combination, with 4a frame, amember formed with a cylindrical pocket, a piston within said pocket,means to control the reciprocating movement of the piston within saidpocket, a member formed with suction and pressure ducts adapted to 'bealtersaid vformed with a cylindrical pocket, a piston nately thrown intocommunication with said pocket, and means to impart relative rotarymovement to said member and frame, said frame forming with said memberav chan 5 ber communicating with said pressure duct through acylindrical passage and in osition to enable the fluid pressure admittedfrom the pressure duct to said chamber to force said member and frameinto engage- 10 ment for tightening said ducts, a pair of plungers#movable Within said cylindrical passage, and elastic means tending topush said plungers apart.

In testimony whereof I hereunto ax my signature in the presence of twowitnesses.,

FRITZ EGERSDRFER..

Witnesses:

E. HOLTZERMAN, R. T. AUSPAER.

